[kn1000]

For the question, just scroll to the bottom~~

Situation: I have one of these really cheap tablet that came pre-rooted and sometimes even displaying ads... The model is S1 from the Oshion brand (again, not a big name) and it is an 8GB tablet.

The thing is, upon checking the storage, I can see two Internal Storages, the first only has ~1GB total and the second has ~4.5GB. When I try installing apps, of course it will be downloaded and installed into the first one first. With such a small storage left (omly 100MB available or so), I can barely update Chrome or even Play Store since it keep giving the "free up space" pop-up message. Seems like installing apps only happened in the first storage...

Now, there are multiple occasions when I don't know how but the tablet decided to install these apps in the second storage (it's not like there's a pop-up asking me where to install it in). I know once installed, I can moved the apps to the second storage if I want to. Though, some are grayed-out, maybe they're the preinstalled apps, or something else that I don't know about. I have transfered all the apps I can on the second storage, still small changes in storage space. Everytime I install something, a pop-up tells me to free up some space.

So I am clueless on how to trigger these apps to install themselves in the second storage. Some of the preinstalled apps even have adwares, but they're rooted into the device since uninstalling them through the traditional way or through some antivirus didn't help (No I'm not putting this here to ask how I can remove these adwares -- I'm fine with them. Just letting everyone know I can't just delete these apps because the next time I reboot they will show up again).

Question: What can I do to make apps install in a second Internal Storage without going through the first one? (or making the second storage my primary destination)